The present invention relates generally to a plasma display panel, and more particularly, to the structure of barrier ribs in the plasma display panel which can improve the whole luminescence and a white balance, simplify processes of manufacturing it, and enhance working steadiness and the reliability of the post process by complementing the different emission characteristics among three Kinds(R, G, and B) of phosphors to be used in the plasma display panel.
FIG. 1 illustrates a schematic partial sectional view of a conventional plasma display panel. As shown in FIG. 1, the plasma display panel comprises a first substrate 11 and a second substrate 21 faced parallel to each other, and barrier ribs 25 formed to maintain the constant distance between the first substrate 11 and the second substrate 21 and to define a discharge space 30. Discharge gas such as Xe, Ne, He, etc., is filled in the discharge space 30. A plurality of first substrate electrodes are arranged in a spaced and parallel relationship to each other on the surface of the first substrate 11 which opposes to the second substrate 21, said first substrate electrodes being formed of complex electrodes 12, 14, 13 and 15 which consist of transparent electrodes 12, 13 and metal electrodes 14 and 15. A dielectric layer 17 and a MgO protective layer 18 are formed thereon in order. Said discharge space 30 defines a plurality of discharge cells and black stripes 16 can also be formed between the adjoining discharge cells.
A plurality of address electrodes 22 are arranged in a spaced and parallel relationship to each other on the surface of the second substrate 21 so as to define a plurality of discharge cells 10 at cross-points of the first substrate electrodes or the complex electrodes 12, 14 and 13, 15. A dielectric layer 27 is formed so as to cover the address electrodes 22, and a phosphor layer 24 is formed so as to cover the side walls of the barrier ribs 25 exposed to the discharging space 30 and the bottom surface of the discharging space 30.
Also, an underlayer 23 may be formed between the address electrodes 22 and the second substrate 21 in order to prevent from being diffused and migrated into adjoining functional layers such as the electrodes, etc., and to enhance the printing characteristics of the functional layers.
By applying predetermined voltages between the complex electrodes 12, 14, 13 and 15 from an alternating current source and forming an electric field in such an alternating current plasma display panel, discharge is performed within each of the discharge cells 10 as a display element, which is separated to each other by the first substrate 11, the second substrate 21 and the barrier ribs 25. And, by ultraviolet rays which are generated during such discharge, the phosphor layer 24 emits visible light which penetrates the first substrate 11 and makes images. Also, the underlayer 23 and the dielectric layer 27 are formed on the second substrate 21 as shown in the illustrative example, but may not be formed if not necessary.
The transparent electrodes 12 and 13 of the first substrate 11 are formed by coating with ITO or SnO2 and then patterning with the photo-etching technology, then the metal electrodes 14 and 15 are formed with Cr/Cu/Cr, Cr/Al/Cr, etc. The other structures such as the dielectric layer 17, the black stripes 16, the barrier ribs 25, etc., are formed with the print technology such as a screen print technology, an offset print technology, etc., the sand blasting, the squeezing technology, the photo-etching technology, etc.
However, there is one problem in a dynamic margin since, among the phosphors generally used for the phosphor layer 24 in the plasma display panel, (Y,Gd)BO3:Eu of R phosphor and BaMgAl10O17:Eu of B phosphor have plus(+) charge characteristics, but Zn2SiO4:Mn of G phosphor has minus(xe2x88x92) charge characteristics, thereby making the discharge voltage higher.
There is also, another problem in that it is very difficult to control a white balance since the characteristics of the phosphors used in the phosphor layer 24 are different from each other as described above.
Meanwhile, in a structure of barrier ribs as illustrated in FIGS. 2a and 2b, the barrier ribs are arranged in a stripe shape and the manufacturing process is simple, but it is a problem that visible light generated by the discharges is leaked out in the stripe direction of the barrier ribs.
Furthermore, in a matrix-structure of barrier rib as illustrated in FIGS. 3a and 3b, it is possible to define each color cell, thereby improving the luminance, to block the leakage of light and to prevent crosstalk in all directions, but its manufacturing is very difficult due to the troublesome process.
Accordingly, in order to the above discussed problems, the present invention provides structures of barrier ribs in the plasma display panel which can improve the whole luminescence and a white balance, simplify processes of manufacturing it, and enhance working stability and the reliability of the post process by complementing the different emission characteristics among three kinds of phosphors(R, G, and B) to be used in the plasma display panel.
To achieve the above-mentioned object, in accordance with one embodiment of the present invention, there is provided a structure of barrier rib in a plasma display panel wherein images are displayed by emitting visible light from three kinds of phosphor(R, G, and B) layers between a plurality of barrier ribs using the discharge phenomenon caused by applying each pulse for scanning and displaying to a plurality of electrodes in order, said structure of barrier ribs being characterized by comprising at least one barrier rib of a half-matrix shape in which protrusions are formed between the barrier ribs.
Said structure of barrier rib further may comprise at least one connection portion to connect the barrier ribs, thereby comprising a matrix-shaped barrier rib in a portion. And, the protrusions in the opposite sides of the half-matrix-shaped barrier rib may be different in width, and/or the half-matrix-shaped barrier rib may be constituted in an arrangement such that widths of the protrusions in the same direction of the half-matrix-shaped barrier rib increase or decrease according to an arrangement of the three Kinds of phosphor(R, G, and B) layers.
Moreover, the half-matrix-shaped barrier rib and widths of the protrusions may be constituted different from each other based on a kind of the phosphor in the phosphor layers, and/or in a relationship with a position on a screen in the plasma display panel.